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' 07 January 2002 AGE-NC Project No 96-0263 ' Page 6 of 7 15-foot section of well screen will be installed in each well, extending approximately 13 feet below ' and 2 feet above the top of the ground water table ' After installing the well casing, filter pack material consisting of pre-washed#3 Lonestar sand will be added from the bottom of the borehole to approximately two feet above the screened intervals Following placement of the filter pack, the well will be surged to assist in settling the filter pack ' Additional sand will be added if settling occurs A nominal two-foot bentonite seal(bentonite chips)will be placed above the filter pack to minimize the potential for grout penetration into the screened section of the well The bentonite seal will be formed by pouring bentonite chips into the annulus and allowing them to settle on the filter pack Bentonite chips will be hydrated using approximately five gallons of tap water The bentonite chips ' will be allowed to hydrate for a minimum of one-half hour prior to grouting The remaining annular space will be filled to the ground surface with a cement grout The grout ' mixture will consist of Type PH portland neat cement and not more than 6 gallons of water per 94-pound sack of cement The grout will be placed by pouring through the augers An inspection . will be scheduled at least 72 hours prior to grouting with PHS-EHD personnel Proposed ground ' water extraction and observation well diagrams are depicted 1n Figures 8 and 9 ' 43 WELL DEVELOPMENT ' Well development will consist of a combination of bailing to remove the major portion of fine- grained sediment from inside each well,surging to flush out or draw in sediment from the filter pack, and additional bailing to finish the removal of sediment Development activities will be continued ' until field parameter (pH, electrical conductivity, and temperature)readings have stabilized ' 4 4 GROUND WATER EXTRACTION (PUMP) TEST A submersible water pump will be utilized to induce a decline in static water level in the proposed ' extraction well(EW-1) Solinst Leveloggers will be deployed in wells EW-1,MW-2,MW-7 and the new observation well to obtain drawdown measurements at 1-minute intervals to measure difference In ground water levels before and during well pumping ' AGE plans to utilize 4 Levelogger Model 3001 instruments to collect the water level data The Leveloggers utilize ceramic pressure transducers to measure water levels The devises record the ' information during the test and can be downloaded to a computer via an RS232 Optical infra-red data reader/port connected to the computer 1 Advanced GeoEnvironmental,Inc